Air conditioning system



Aug 2, 193%, c. W. NESSELL AIR CONDITIONING SYSTEM Filed July 12, 1957 INVENTOR 7' I Clarence WA/ssell ATTORNEY Patented Aug. 2,, i938 uurrso stares PATENT- OFFICE AIR, CONDITIONING EJYSTEM Clarence W. Nessell, Dayton, Ohio, assignor to Minneapolis-Honeywell Regulator Company, Minneapolis, Minn, a corporation of Delaware Application July 12, 1937, Serial No. 153,095

' 6 Claims. (Cl. 98-39) The present invention relates to a system of air open, the distribution or balance is upset. This circulation through an air conditioning chammeans that while the main controlling compartber and into aplurality of spaces to be conment is maintained at the desired temperature, ditioned, and while it is illustrated and described the other compartments may be maintained at s in connection with awarm air heating system, mp ratures whi h re ei hi her r wer it is of course equally applicable toother forms than contemplated and desired. of air conditioning systems. One of the objects of the present invention is The invention described and claimed herein the provision of a system of distributing fluid to is designed as an improvement or simplification a plurality of points of use having diflferent re- 10 of the system disclosed by application Serial No. quirements in which the distribution system is v1o 707,080, filed January 18, 1934, by Arthur C. arranged to give the proper distribution of fluid Grant, and eliminates the necessity for using to all of the points of use when all of them are certain equipment which might be too expensive in operation, together with means for automaticfor a small home installation, while achieveally maintaining the p op s but on to the ing the same desired results. remaining points of use when one or more of 15 In a warm air heating system, it is usual to the points of use is rendered inoperative. provides. warm air furnace or other means for A further object of the invention is the proheating the air, together with pipes or ducts for vision of an air distribution system wherein air leading the heated air to the various compartis adapted to be distributed through properly ments to be heated. It is well recognized that arranged ducts or pipes so that different desired Various compartments q e Varying Volumes flows or volumes of air are delivered to the deheated p r t of ime y re o of difsired points, together with means for automaticferences in size,.difierences in heat loss and, in ally maintaining the same flow through those some instances, because it is desired to maintain d t un i operation when some of the ducts v n empe ures in. vari us ompar men are closed off so as to prevent "the flow oi air 25 In order to obviate the necessity of separate therethrough, n ro in means o cflntrolling the w of Another object of the invention is the provision to each Of e Compartments, it has been usual of a warm air heating system of the type wherein to provide a single control responsive to the term a plurality of ducts leading to a plurality of H m of y One Of the compartments Wherecompartments to be heated are proportioned or 30 by the temperature of t Compartment is mainarranged to give the desired flow or volume or tained at the desired point and to maintain the proportion of air t h a d every one of the desired temperatures in the other compartments compartments h ,111 of the ducts are open by arranging the ducts or Pipes in Such manner to the passage of air and means for maintaining that the proper amount of heated air is this proper proportion or flow or volume to those at tributed to each of these compartments. This is ducts still i gperation h n one or more of generally c omplished by p id ducts of them is placed out of operation and the flow of different sizes and in some instances additional air therethrough b t t d,

means such as individual dampers are also pro- More specifically an object of the present -10 vided in order that the proportional amount of vention is the provision of a fluid distribution to the total air delivered to each compartment in system by which varying volumes of fluid are response to the control in the controlling delivered per unit of time to a plurality of points partmem may be propeljly adlusted' of use having different volume requirements, and such Systems are sansfactory when an 9 the providing automatic means for maintaining the -15 ducts are open so that the proper balance in the delivery pressure constant whereby when id g? a an of the fi f 1:; livery oi fluid to one of said points is obstructed, m m y reason 0 e a mm the volume delivered to the remaining points per proper design of the ducts. However, it 15 often unit of time remains constant desired to block; off the flow of air to one or more of the compartments. When this is done, Furthei oblects of the mvention Wm be found 50 approximately th same t t volume f air is in the detailed description, the appended claims then available for a lesser number of compartand the drawmgmerits and inasmuch as the ducts have been=ar- F a m r complete understanding of e inranged to give the proper flow of air to each vention, reference may be had to the following so compartment only when all of the ducts are detailed description and the accompanying single drawing, which is a diagrammatic showing of one application of the instant invention.

Referring to this single drawing, the invention is shown as applied to a warm air heating system which includes a warm air furnace generally indicated at I0, having a combustion chamber I and a warm air heating chamber 16. The heat output of the furnace is shown as being controlled by the ordinary draft damper I l and usual check damper l2. Air is supplied to the furnace ID by means of a return pipe l3 which communicates with a blower 14, preferably electrically operated. The blower discharges this air into the furnace l0 through a pipe or duct 15. Theair then flows through the furnace and into the usual warm air heating chamber 16 thereof, where the air is,

' connects with the air heating chamber 16 and a register 22 located in the room H. The room l9 as shown requires a smaller amount of heat per unit of time as indicated by the fact that the duct 23 leading from air heating chamber It to the register 24 of room I! is slightly smaller than the duct 2|. In a similar manner, two progressively smaller ducts 25 and 26 lead from air heating chamber It. to registers 21 and 28 located respectively in rooms 13 and 20. Each of the registers is provided with the usual shutter 29 whereby any one of the ducts 2|. 25, 23 or 26 may be shut off so as to interrupt the flow of air therethrough and to the corresponding room l1, l8, 19 or 20.

With the arrangement thus far described, the ducts 2|, 25, 23 and 26 have been proportioned in such manner that when all of them are open to the flow of air, the proper proportional part of the total air delivered by the blower l4 and heated by the furnace III will be delivered to each of the rooms. With no additional mechanism, 11' the register 22 leading to room I! were shut off, the total amount of air delivered by blower I! would thereupon be distributed to the three remaining rooms l3, l3 and 20. This would result in an increase in the velocity of the air flowing through the respective ducts 23, 25 and 26. Such an increase in velocity is undesirable for several reasons. For one thing, the velocity of air flowing into the room has a bearing upon-the quickness of response upon the main controlling thermostat located in some one of the rooms with the result that changes in velocity of the air delivered to the rooms results in changes in the response of the heating system. Furthermore, an increased velocity may set up an increased circulation within the room itself to such an extent as to make the occupants ther'eof uncomfortable. Also, the velocity may increase to such an extent as to cause undesirable, noises. Furthermore, and most important, is the fact that because the remaining three ducts 23, 25 and 26 have different sizes, and therefore different resistances, the distribution of air or the proportion of the total air distributed to each 01' the remaining rooms 18, i9 and 20 will change from that desired and contemplated in originally laying out the heating system so that the desired temperatures will not be maintained in those rooms which do not contain the control device.

To overcome these detrimental effects, I provide a by-pass 32 providing communication between the heating chamber and return pipe l3. Located at the junction between the by-pass 32 and the heating chamber is a damper 30 pivoted at its upper end and provided with a weight 3| at its lower end. This damper and its weight are designed to close the by-pass 32 when all the registers 29 are open. With the parts in the position shown in the drawing, all of the ducts 2|, 25, 23 and26 are open and the damper 30 is in closed position, preventing any flow of air through the by-pass 32, the air pressure being insufficient to open the damper. If one of the registers, such as 22, is closed, preventing flow of air through duct 2| into room H, the pressure through the remaining ducts 25, 23 and 25 and in the heating chamber will tend to increase. This will cause damper 30 to move toward the dotted line position an amount sufiicient to permit enough air to pass throughby-pass 32 so that the pressure through the ducts 25, 23 and 26 will remain constant. In this manner there will always be a constant flow of air through whichever of the ducts 2|, 25, 23 and 26 may happen to be open, so that the amount of air delivered to each room per unit of time always remains constant when its respective duct is open. It therefore follows that the proportion of air delivered to each of the rooms will likewise remain constant. It is contemplated that the draft damper I l and the check damper l2, as well as the blower M, will be controlled by a thermostat located in some one of the compartments l1, l8, l9 or 20 in any well-khown manner, such as that disclosed in Edward F. Edgecombe, Jr. Patent Re. 15,531, which issued January 23, 1923.

Having described my invention in its preferred embodiment, I wish it to be understood that many changes can be made by those skilled in the art without departing from the spirit of the invention, and I therefore intend to be limited only by the scope of the appended claims.

.. I claim as my invention:

1. In an air conditioning system, an air conditioning chamber, a delivery duct 'connecting said chamber to a space to be conditioned, means for recirculating air through said chamber, duct, and space, said means including a fan having its outlet in communication with the chamber, a conduit through which return air from said space passes to the fan inlet, and a second conduit connecting said first conduit directly tosaid chamber, said second conduit forming a by-pass from said chamber to said fan inlet, means to adjust the eflective area of said delivery duct, and means in said second conduit, responsive to a change in the effective area of said delivery duct,

-to change the area of said second conduit an amount sumcient to maintain the pressure of air through said delivery duct substantially constant at all times during operation of the system.

2. In an air conditioning system, an air conditioning chamber, a plurality of delivery ducts connecting said chamber to a plurality of spaces to be conditioned, means for recirculating air through said chamber, ducts and spaces to be conditioned, said means including a fan having its outlet in communication with the chamber, a conduit through which return air from said spaces passes to the fan inlet, and a second conduit connecting said first conduit directly to said chamber, said second conduit forming a by-pass 2,125,646 irom said chamber to said fan inlet, means to adjust the effective area of at least one of said ducts, a hinged damper in said second conduit, said hinged damper being arranged to change the efiective area of said conduit in response to a change in the efiective area of said delivery ducts an amount sufiicient to maintain the air pressure in said delivery ducts substantially constant at all times during operation of the system.

3. In a heating system, in combination, a heating chamber, a plurality of delivery ducts connecting, said chamber to a plurality of spaces to be heated, an inlet duct for said heating chamber, fan means arranged to draw air through said inlet duct, and force it through said chamber, delivery ducts, and into the spaces to be heated, means to adjust the effective area of at least one of said ducts, a by-pass from the heating chamber to the fan inlet, and means in said by-pass, re-

sponsive to a change in the efiective area of any of said delivery ducts, to change the effective area of said by-pass an amount sufiicient to maintain the pressure of air through said delivery ducts substantially constant at all times during operation of the system.

4. In a heating system, in combination, a heatlng chamber, a plurality of delivery ducts connecting said chamber to a plurality of spaces to be heated, an inlet duct for said heating chamber, fan means arranged to draw air through said inlet duct, and force it through said chamber, delivery ducts, and into the spaces to be heated, means to adjust the effective area of at least one of said delivery ducts, a by-pass from the heating chamber to the fan inlet, a hinged damper in said by-pass, said damper being arranged to change the efiective area of said by-pass in response to a change in the effective area of said delivery ducts, an amount sumcient to maintain the air pressure in said delivery ducts substantially constant at all times during operation of the system.

5. In an air conditioning system, in combination, an air conditioning chamber, duct means connecting said chamber to a plurality of spaces to be conditioned requiring difierent amounts of conditioned air per unit of time, an inlet duct for said air conditioning chamber, fan means arranged to draw air through saidinlet duct, and force it through said chamber and said duct means into the spaces to be conditioned, means to restrict the effective area of at least a portion of said duct means, a by-pass'from the air conditioning chamber to the fan inlet, and means in said by-pass, responsive to a change in the efiective area of said duct means, to change the area of by-pass an amount sumcient to maintain the pressure of air through said duct means substantially constant at all times during operation of the system.

6. In an air conditioning system, in combination, an air conditioning chamber, duct means connecting said chamber to a plurality of spaces to be conditioned requiring different amounts of conditioned air per unit of time,"an inlet duct for said air conditioning chamber, fan means arranged to draw air through said inlet duct, and

force it through said chamber and said duct means into the spaces to be conditioned, means to restrict the effective area of at least a portion 

